Micro Motion Guide: Guidelines for the Selection and Operation of Provers with ELITE Coriolis Flow Meters | Micro Motion Manuals & Guides

Reference Guide

MC-001597 Rev E

1/2018

ELITE® Coriolis Flow Meters

Guidelines for the Selection and Operation
of Provers with Micro Motion ELITE

®

Coriolis

Flow Meters

Micro Motion® ELITE® ow meters are high-

precision Coriolis ow meters that are often used
in the oil and gas industry in conjunction with
volume provers. These guidelines are designed to
aid in the selection of a prover size that will result
in consistent proving repeatability, while taking
into consideration the balance between:

• Maximum proving efciency

• Minimum prover size and cost

• Minimum prover wear and maintenance

Substantial experience from laboratory testing and
eld proving forms the basis of the prover size
recommendations and the Total Prove Time (TPT)
predictions in these guidelines. However, results
may vary if unstable process conditions exist
during proving.

It should be noted that these guidelines are based
on conservative estimates from the available data.
If repeatability requirements are already consis­tently being met, there is no need to change the
process or the prover size.

Proving Methods and Proving Data Evaluation

The American Petroleum Industry (API) Manual
of Petroleum Measurement Standards (MPMS)
Chapter 4.8, Second Edition, Operation of Proving
Systems, Annex A, Evaluating Meter Proving
Data explains the relationship between the number

of proving runs, the observed repeatability, and the
random uncertainty of the resulting meter factor.
One important principal is that a lower meter factor
uncertainty will always result as more runs are
collected and averaged.

Prover Sizing and Selection for Fixed­Volume Provers (Does Not Apply to Master
Meter Provers)

Important Note: The prover size should never
result in a pass time of less than 0.5 seconds or
a pre-run time of less than 0.25 seconds.

Total Prove Time (TPT) is dened as the total

accumulated amount of time during which the
prover displacer was travelling between the detector
switches. The minimum TPT that is needed to
achieve the target meter factor random uncertainty
can be used to size the prover.

Estimated minimum TPT values that may be
expected to pass repeatability requirements for

different meter sizes and ow rates are shown in
Table 1. The velocity of the uid as it travels through
the meter ow tubes is also shown in Table 1 in

units of feet per second (fps). Velocities above
60 fps are not recommended when proving with

a xed-volume prover and may result in excessive

TPT to pass repeatability. For applications above
60 fps, master meter proving is recommended
instead of xed-volume provers.

Equation 1 describes TPT:

www.Emerson.com/MicroMotion

Base Prover Volume(BPV)

𝑇𝑃𝑇 

Flow rate

×(# 𝑜 𝑟𝑢𝑛𝑠󰇜 × (# 𝑜 𝑝𝑎𝑠𝑠𝑒𝑠 𝑝𝑒𝑟 𝑟𝑢𝑛󰇜

Reference Guide

MC-001597 Rev E

1/2018

ELITE® Coriolis Flow Meters

To use Table 1 to size a prover, there are two
methods to select from:

Method 1 (Determine the BPV): Find the minimum

TPT value from Table 1. Multiply the ow rate by

0.0117 to convert from BPH to gallons per second.
Then enter the TPT, ow rate, the number of runs,

and the passes per run (if averaging multiple passes

per run) into Equation 2 to nd the minimum BPV

needed in gallons.

Equation 2:

𝐵𝑃 

TPT x Flow Rate

(# 𝑜 R𝑢𝑛𝑠󰇜×(Passes pe Run󰇜

Example: CMFHC4 meter at 6500 BPH

• From Table 1: Velocity ≈ 30 fps. TPT =

20 seconds.

• Convert: 6500 BPH X 0.0117 = 76 gallons
per second

• If 5 single-pass runs are required, BPV =
(20 seconds X 76 gallons per second)
÷ (5 runs X 1 pass per run) = 304 gallons
or 7.2 BBLS.

• If 10 runs and 3 passes per run are acceptable,
BPV = (20 seconds X 76 gallons per second) ÷
(10 runs X 3 pass per run) = 50 gallons or

1.2 BBLS.

Method 2 (Determine the Number of Passes
Needed): Find the minimum TPT value from

Table 1. Multiply the ow rate by 0.0117 to convert
from BPH to gallons per second. Then, insert
the ow rate and a BPV in gallons into Equation

3 to estimate the total number of passes that

will be needed for a prover size with that BPV. If

averaging multiple passes per run, divide the total
number of passes needed by the number of runs
and round up to determine the minimum number

of passes per run needed. For single-pass runs,

the number of runs needed will equal the total
number of passes needed.

Equation 3:

𝑇𝑜𝑡𝑎 # 𝑜 𝑃𝑎𝑠𝑠𝑒𝑠  𝑇𝑃𝑇×

Flow rate

Base Prover Volume(BPV)

Example: CMF400 meter at 2300 BPH

• From Table 1: Velocity ≈ 40 fps. TPT ≈

30 seconds.

• Convert: 2300 BPH X 0.0117 = 27 gallons
per second

• If the BPV is 170 gallons (4 BBLS), Total #
of passes = 30 seconds X 27 gallons per
second ÷ 170 gallons = 5 total passes

(5 total passes ÷ 5 runs = 1 pass per run

for 5 runs).

Page 2

• If the BPV is 65 gallons (1.55 BBLS), Total # of
passes = 30 seconds X 27 gallons per second
÷ 65 gallons = 12 total passes

(12 total passes ÷ 5 runs = 3 passes per
run for 5 runs).